***2018 ZOONOSIS OF CHRONIC WASTING DISEASE CWD TSE PRION***
Cervid to human prion transmission
Kong, Qingzhong
Case Western Reserve University, Cleveland, OH, United States
Abstract
Prion disease is transmissible and invariably fatal. Chronic wasting disease (CWD) is the prion disease affecting deer, elk and moose, and it is a widespread and expanding epidemic affecting 22 US States and 2 Canadian provinces so far. CWD poses the most serious zoonotic prion transmission risks in North America because of huge venison consumption (>6 million deer/elk hunted and consumed annually in the USA alone), significant prion infectivity in muscles and other tissues/fluids from CWD-affected cervids, and usually high levels of individual exposure to CWD resulting from consumption of the affected animal among often just family and friends. However, we still do not know whether CWD prions can infect humans in the brain or peripheral tissues or whether clinical/asymptomatic CWD zoonosis has already occurred, and we have no essays to reliably detect CWD infection in humans.
We hypothesize that:
(1) The classic CWD prion strain can infect humans at low levels in the brain and peripheral lymphoid tissues;
(2) The cervid-to-human transmission barrier is dependent on the cervid prion strain and influenced by the host (human) prion protein (PrP) primary sequence;
(3) Reliable essays can be established to detect CWD infection in humans; and
(4) CWD transmission to humans has already occurred. We will test these hypotheses in 4 Aims using transgenic (Tg) mouse models and complementary in vitro approaches.
Aim 1 will prove that the classical CWD strain may infect humans in brain or peripheral lymphoid tissues at low levels by conducting systemic bioassays in a set of humanized Tg mouse lines expressing common human PrP variants using a number of CWD isolates at varying doses and routes. Experimental human CWD samples will also be generated for Aim 3.
Aim 2 will test the hypothesis that the cervid-to-human prion transmission barrier is dependent on prion strain and influenced by the host (human) PrP sequence by examining and comparing the transmission efficiency and phenotypes of several atypical/unusual CWD isolates/strains as well as a few prion strains from other species that have adapted to cervid PrP sequence, utilizing the same panel of humanized Tg mouse lines as in Aim 1.
Aim 3 will establish reliable essays for detection and surveillance of CWD infection in humans by examining in details the clinical, pathological, biochemical and in vitro seeding properties of existing and future experimental human CWD samples generated from Aims 1-2 and compare them with those of common sporadic human Creutzfeldt-Jakob disease (sCJD) prions.
Aim 4 will attempt to detect clinical CWD-affected human cases by examining a significant number of brain samples from prion-affected human subjects in the USA and Canada who have consumed venison from CWD-endemic areas utilizing the criteria and essays established in Aim 3. The findings from this proposal will greatly advance our understandings on the potential and characteristics of cervid prion transmission in humans, establish reliable essays for CWD zoonosis and potentially discover the first case(s) of CWD infection in humans.
Public Health Relevance
There are significant and increasing human exposure to cervid prions because chronic wasting disease (CWD, a widespread and highly infectious prion disease among deer and elk in North America) continues spreading and consumption of venison remains popular, but our understanding on cervid-to-human prion transmission is still very limited, raising public health concerns. This proposal aims to define the zoonotic risks of cervid prions and set up and apply essays to detect CWD zoonosis using mouse models and in vitro methods. The findings will greatly expand our knowledge on the potentials and characteristics of cervid prion transmission in humans, establish reliable essays for such infections and may discover the first case(s) of CWD infection in humans.
NIH 2015 R01 NS Cervid to human prion transmission Kong, Qingzhong / Case Western Reserve University $337,507
ZOONOTIC CHRONIC WASTING DISEASE CWD TSE PRION UPDATE
here is the latest;
PRION 2018 CONFERENCE
Oral transmission of CWD into Cynomolgus macaques: signs of atypical disease, prion conversion and infectivity in macaques and bio-assayed transgenic mice
Hermann M. Schatzl, Samia Hannaoui, Yo-Ching Cheng, Sabine Gilch (Calgary Prion Research Unit, University of Calgary, Calgary, Canada) Michael Beekes (RKI Berlin), Walter Schulz-Schaeffer (University of Homburg/Saar, Germany), Christiane Stahl-Hennig (German Primate Center) & Stefanie Czub (CFIA Lethbridge). To date, BSE is the only example of interspecies transmission of an animal prion disease into humans. The potential zoonotic transmission of CWD is an alarming issue and was addressed by many groups using a variety of in vitro and in vivo experimental systems. Evidence from these studies indicated a substantial, if not absolute, species barrier, aligning with the absence of epidemiological evidence suggesting transmission into humans. Studies in non-human primates were not conclusive so far, with oral transmission into new-world monkeys and no transmission into old-world monkeys. Our consortium has challenged 18 Cynomolgus macaques with characterized CWD material, focusing on oral transmission with muscle tissue. Some macaques have orally received a total of 5 kg of muscle material over a period of 2 years.
After 5-7 years of incubation time some animals showed clinical symptoms indicative of prion disease, and prion neuropathology and PrPSc deposition were detected in spinal cord and brain of some euthanized animals. PrPSc in immunoblot was weakly detected in some spinal cord materials and various tissues tested positive in RT-QuIC, including lymph node and spleen homogenates. To prove prion infectivity in the macaque tissues, we have intracerebrally inoculated 2 lines of transgenic mice, expressing either elk or human PrP. At least 3 TgElk mice, receiving tissues from 2 different macaques, showed clinical signs of a progressive prion disease and brains were positive in immunoblot and RT-QuIC. Tissues (brain, spinal cord and spleen) from these and pre-clinical mice are currently tested using various read-outs and by second passage in mice. Transgenic mice expressing human PrP were so far negative for clear clinical prion disease (some mice >300 days p.i.). In parallel, the same macaque materials are inoculated into bank voles.
Taken together, there is strong evidence of transmissibility of CWD orally into macaques and from macaque tissues into transgenic mouse models, although with an incomplete attack rate.
The clinical and pathological presentation in macaques was mostly atypical, with a strong emphasis on spinal cord pathology.
Our ongoing studies will show whether the transmission of CWD into macaques and passage in transgenic mice represents a form of non-adaptive prion amplification, and whether macaque-adapted prions have the potential to infect mice expressing human PrP.
The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD..
***> The notion that CWD can be transmitted orally into both new-world and old-world non-human primates asks for a careful reevaluation of the zoonotic risk of CWD. <***
THURSDAY, DECEMBER 06, 2018
Mississippi Fourth CWD TSE Prion Suspected in Marshall County Mississippi White-tailed Deer 12/6/2018 3:16:02 PM From MDWFP
READING OVER THE PRION 2018 ABSTRACT BOOK, LOOKS LIKE THEY FOUND THAT from this study ;
P190 Human prion disease mortality rates by occurrence of chronic wasting disease in freeranging cervids, United States
Abrams JY (1), Maddox RA (1), Schonberger LB (1), Person MK (1), Appleby BS (2), Belay ED (1) (1) Centers for Disease Control and Prevention (CDC), National Center for Emerging and Zoonotic Infectious Diseases, Atlanta, GA, USA (2) Case Western Reserve University, National Prion Disease Pathology Surveillance Center (NPDPSC), Cleveland, OH, USA..
SEEMS THAT THEY FOUND Highly endemic states had a higher rate of prion disease mortality compared to non-CWD states.
AND ANOTHER STUDY;
P172 Peripheral Neuropathy in Patients with Prion Disease
Wang H(1), Cohen M(1), Appleby BS(1,2) (1) University Hospitals Cleveland Medical Center, Cleveland, Ohio (2) National Prion Disease Pathology Surveillance Center, Cleveland, Ohio..
IN THIS STUDY, THERE WERE autopsy-proven prion cases from the National Prion Disease Pathology Surveillance Center that were diagnosed between September 2016 to March 2017,
AND
included 104 patients. SEEMS THEY FOUND THAT The most common sCJD subtype was MV1-2 (30%), followed by MM1-2 (20%),
AND
THAT The Majority of cases were male (60%), AND half of them had exposure to wild game.
snip...see more on Prion 2017 Macaque study from Prion 2017 Conference and other updated science on cwd tse prion zoonosis below...terry
WITH the recent findings that Scrapie will transmit to Macaque by oral route, that Scrapie and CWD TSE Prion will transit to pigs orally, recent outbreak documented of TSE Prion Disease in Dromedary Camels, Algeria, atypical TSE Prion still being documented, and again just recently in the USA, of another atypical BSE case, and this discovery was only documented by testing 20k head of cattle from some 100M head of cattle in any given year in the USA, the continued denial that atypical BSE and atypical Scrapie are a transmissible disease (science has shown otherwise) this is concerning to me. Science and scientific policy makers have forgotten what Gibbs, Gajdusek, Hadlow, Alper, Zigas, even Gordon with the infamous Scrapie vaccine blunder, a discovery of valuable importance, and so many others i am failing to remember now, what some found long ago, like Dr. Gibbs, he tried to warn us about scrapie zoonosis potential, yet that went ignored for decades and decades. we/scientist/officials/the world, knows the USA FDA PART 589 TSE PRION FEED ban has failed terribly, the BSE testing has failed terribly, and the surveillance there from has failed, SRM removal breaches, all proven by the OIG or the GAO, and others. But yet, we find ourselves now debating the issue of these same risk factors for scrapie, the same risk factors that we all knew were there, with science staring us in the face, we still deny scientific facts all in the name of corporate interest. let's not continue to make these same mistakes. human and animal life is at stake here. we must remove corporate/government/lobbyist interest from the scientific policy making and regulations there from for the TSE Prion, all of them. ...Terry S. Singeltary SR.
O3 Experimental studies on prion transmission barrier and TSE pathogenesis in large animals
Rosa Bolea(1), Acín C(1)Marín B(1), Hedman C(1), Raksa H(1), Barrio T(1), Otero A(1), LópezPérez O(1), Monleón E(1),Martín-Burriel(1), Monzón M(1), Garza MC(1), Filali H(1),Pitarch JL(1), Garcés M(1), Betancor M(1), GuijarroIM(1), GarcíaM(1), Moreno B(1),Vargas A(1), Vidal E(2), Pumarola M(2), Castilla J(3), Andréoletti O(4), Espinosa JC(5), Torres JM(5), Badiola JJ(1).
1Centro de Investigación en Encefalopatías y Enfermedades Transmisibles Emergentes, VeterinaryFaculty, Universidad de Zaragoza; Zaragoza,Spain.2 RTA, Centre de Recerca en Sanitat Animal (CReSA, IRTA-UAB) 3 4 INRA, ÉcoleVétérinaire, Toulouse, France.5CIC bioGUNE, Prion researchlab, Derio, Spain CISA- INIA, Valdeolmos, Madrid 28130, Spain.
Experimental transmission of Transmissible Spongiform Encephalopathies (TSE) has been understood and related with several factors that could modify the natural development of these diseases. In fact, the behaviour of the natural disease does not match exactly in each animal, being modified by parameters such as the age at infection, the genotype, the breed or the causative strain. Moreover, different TSE strains can target different animal species or tissues, what complicate the prediction of its transmissibility when is tested in a different species of the origin source. The aim of the experimental studies in large animals is to homogenize all those factors, trying to minimize as much as possible variations between individuals. These effects can be flattened by experimental transmission in mice, in which a specific strain can be selected after several passages. With this objective, several experimental studies in large animals have been developed by the presenter research team.
Classical scrapie agent has been inoculated in cow, with the aim of demonstrate the resistance or susceptibility of this species to the first well known TSE; Atypical scrapie has been inoculated in sheep (using several routes of infection), cow and pig, with the objective of evaluating the potential pathogenicity of this strain; Classical Bovine Spongiform Encephalopathy (BSE) has been inoculated in goats aiming to demonstrate if the genetic background of this species could protect against this strain; goat BSE and sheep BSE have been inoculated in goats and pigs respectively to evaluate the effect of species barrier; and finally atypical BSE has been inoculated in cattle to assess the transmissibility properties of this newly introduced strain.
Once the experiments have been carried out on large animal species, a collection of samples from animals studied were inoculated in different types of tg mice overexpressing PrPcin order to study the infectivity of the tissues, and also were studied using PMCA.
In summary, the parameters that have been controlled are the species, the strain, the route of inoculation, the time at infection, the genotype, the age, and the environmental conditions.
To date,
***> eleven of the atypical scrapie intracerebrally inoculated sheep have succumbed to atypical scrapie disease;
***> six pigs to sheep BSE;
***> one cow to classical scrapie;
***> nine goats to goat BSE and
***> five goats to classical BSE.
***> PrPSC has been demonstrated in all cases by immunohistochemistry and western blot.
=====> PRION CONFERENCE 2018
why do we not want to do TSE transmission studies on chimpanzees $
5. A positive result from a chimpanzee challenged severly would likely create alarm in some circles even if the result could not be interpreted for man.
***> I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough.
***> Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.
snip...
ZOONOSIS OF SCRAPIE TSE PRION
O.05: Transmission of prions to primates after extended silent incubation periods: Implications for BSE and scrapie risk assessment in human populations
Emmanuel Comoy, Jacqueline Mikol, Valerie Durand, Sophie Luccantoni, Evelyne Correia, Nathalie Lescoutra, Capucine Dehen, and Jean-Philippe Deslys Atomic Energy Commission; Fontenay-aux-Roses, France
Prion diseases (PD) are the unique neurodegenerative proteinopathies reputed to be transmissible under field conditions since decades. The transmission of Bovine Spongiform Encephalopathy (BSE) to humans evidenced that an animal PD might be zoonotic under appropriate conditions. Contrarily, in the absence of obvious (epidemiological or experimental) elements supporting a transmission or genetic predispositions, PD, like the other proteinopathies, are reputed to occur spontaneously (atpical animal prion strains, sporadic CJD summing 80% of human prion cases).
Non-human primate models provided the first evidences supporting the transmissibiity of human prion strains and the zoonotic potential of BSE. Among them, cynomolgus macaques brought major information for BSE risk assessment for human health (Chen, 2014), according to their phylogenetic proximity to humans and extended lifetime. We used this model to assess the zoonotic potential of other animal PD from bovine, ovine and cervid origins even after very long silent incubation periods.
*** We recently observed the direct transmission of a natural classical scrapie isolate to macaque after a 10-year silent incubation period,
***with features similar to some reported for human cases of sporadic CJD, albeit requiring fourfold long incubation than BSE. Scrapie, as recently evoked in humanized mice (Cassard, 2014),
***is the third potentially zoonotic PD (with BSE and L-type BSE),
***thus questioning the origin of human sporadic cases.
We will present an updated panorama of our different transmission studies and discuss the implications of such extended incubation periods on risk assessment of animal PD for human health.
===============
***thus questioning the origin of human sporadic cases***
===============
***our findings suggest that possible transmission risk of H-type BSE to sheep and human. Bioassay will be required to determine whether the PMCA products are infectious to these animals.
==============
***Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice.
***Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
***These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
PRION 2016 TOKYO
Saturday, April 23, 2016
SCRAPIE WS-01: Prion diseases in animals and zoonotic potential 2016
Prion. 10:S15-S21. 2016 ISSN: 1933-6896 printl 1933-690X online
Taylor & Francis
Prion 2016 Animal Prion Disease Workshop Abstracts
WS-01: Prion diseases in animals and zoonotic potential
Juan Maria Torres a, Olivier Andreoletti b, J uan-Carlos Espinosa a. Vincent Beringue c. Patricia Aguilar a,
Natalia Fernandez-Borges a. and Alba Marin-Moreno a
"Centro de Investigacion en Sanidad Animal ( CISA-INIA ). Valdeolmos, Madrid. Spain; b UMR INRA -ENVT 1225 Interactions Holes Agents Pathogenes. ENVT. Toulouse. France: "UR892. Virologie lmmunologie MolécuIaires, Jouy-en-Josas. France
Dietary exposure to bovine spongiform encephalopathy (BSE) contaminated bovine tissues is considered as the origin of variant Creutzfeldt Jakob (vCJD) disease in human. To date, BSE agent is the only recognized zoonotic prion... Despite the variety of Transmissible Spongiform Encephalopathy (TSE) agents that have been circulating for centuries in farmed ruminants there is no apparent epidemiological link between exposure to ruminant products and the occurrence of other form of TSE in human like sporadic Creutzfeldt Jakob Disease (sCJD). However, the zoonotic potential of the diversity of circulating TSE agents has never been systematically assessed. The major issue in experimental assessment of TSEs zoonotic potential lies in the modeling of the ‘species barrier‘, the biological phenomenon that limits TSE agents’ propagation from a species to another. In the last decade, mice genetically engineered to express normal forms of the human prion protein has proved essential in studying human prions pathogenesis and modeling the capacity of TSEs to cross the human species barrier.
To assess the zoonotic potential of prions circulating in farmed ruminants, we study their transmission ability in transgenic mice expressing human PrPC (HuPrP-Tg). Two lines of mice expressing different forms of the human PrPC (129Met or 129Val) are used to determine the role of the Met129Val dimorphism in susceptibility/resistance to the different agents.
These transmission experiments confirm the ability of BSE prions to propagate in 129M- HuPrP-Tg mice and demonstrate that Met129 homozygotes may be susceptible to BSE in sheep or goat to a greater degree than the BSE agent in cattle and that these agents can convey molecular properties and neuropathological indistinguishable from vCJD. However homozygous 129V mice are resistant to all tested BSE derived prions independently of the originating species suggesting a higher transmission barrier for 129V-PrP variant.
Transmission data also revealed that several scrapie prions propagate in HuPrP-Tg mice with efficiency comparable to that of cattle BSE. While the efficiency of transmission at primary passage was low, subsequent passages resulted in a highly virulent prion disease in both Met129 and Val129 mice.
Transmission of the different scrapie isolates in these mice leads to the emergence of prion strain phenotypes that showed similar characteristics to those displayed by MM1 or VV2 sCJD prion.
These results demonstrate that scrapie prions have a zoonotic potential and raise new questions about the possible link between animal and human prions.
why do we not want to do TSE transmission studies on chimpanzees $
5. A positive result from a chimpanzee challenged severly would likely create alarm in some circles even if the result could not be interpreted for man.
***> I have a view that all these agents could be transmitted provided a large enough dose by appropriate routes was given and the animals kept long enough.
***> Until the mechanisms of the species barrier are more clearly understood it might be best to retain that hypothesis.
snip...
R. BRADLEY
Title: Transmission of scrapie prions to primate after an extended silent incubation period)
*** In complement to the recent demonstration that humanized mice are susceptible to scrapie, we report here the first observation of direct transmission of a natural classical scrapie isolate to a macaque after a 10-year incubation period. Neuropathologic examination revealed all of the features of a prion disease: spongiform change, neuronal loss, and accumulation of PrPres throughout the CNS.
*** This observation strengthens the questioning of the harmlessness of scrapie to humans, at a time when protective measures for human and animal health are being dismantled and reduced as c-BSE is considered controlled and being eradicated.
*** Our results underscore the importance of precautionary and protective measures and the necessity for long-term experimental transmission studies to assess the zoonotic potential of other animal prion strains.
***> Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility. <***
Transmission of scrapie prions to primate after an extended silent incubation period
Emmanuel E. Comoy, Jacqueline Mikol, Sophie Luccantoni-Freire, Evelyne Correia, Nathalie Lescoutra-Etchegaray, Valérie Durand, Capucine Dehen, Olivier Andreoletti, Cristina Casalone, Juergen A. Richt, Justin J. Greenlee, Thierry Baron, Sylvie L. Benestad, Paul Brown & Jean-Philippe Deslys Scientific Reports volume 5, Article number: 11573 (2015) | Download Citation
Abstract
Classical bovine spongiform encephalopathy (c-BSE) is the only animal prion disease reputed to be zoonotic, causing variant Creutzfeldt-Jakob disease (vCJD) in humans and having guided protective measures for animal and human health against animal prion diseases. Recently, partial transmissions to humanized mice showed that the zoonotic potential of scrapie might be similar to c-BSE. We here report the direct transmission of a natural classical scrapie isolate to cynomolgus macaque, a highly relevant model for human prion diseases, after a 10-year silent incubation period, with features similar to those reported for human cases of sporadic CJD. Scrapie is thus actually transmissible to primates with incubation periods compatible with their life expectancy, although fourfold longer than BSE. Long-term experimental transmission studies are necessary to better assess the zoonotic potential of other prion diseases with high prevalence, notably Chronic Wasting Disease of deer and elk and atypical/Nor98 scrapie.
SNIP...
Discussion We describe the transmission of spongiform encephalopathy in a non-human primate inoculated 10 years earlier with a strain of sheep c-scrapie. Because of this extended incubation period in a facility in which other prion diseases are under study, we are obliged to consider two alternative possibilities that might explain its occurrence. We first considered the possibility of a sporadic origin (like CJD in humans). Such an event is extremely improbable because the inoculated animal was 14 years old when the clinical signs appeared, i.e. about 40% through the expected natural lifetime of this species, compared to a peak age incidence of 60–65 years in human sporadic CJD, or about 80% through their expected lifetimes. Moreover, sporadic disease has never been observed in breeding colonies or primate research laboratories, most notably among hundreds of animals over several decades of study at the National Institutes of Health25, and in nearly twenty older animals continuously housed in our own facility.
The second possibility is a laboratory cross-contamination. Three facts make this possibility equally unlikely. First, handling of specimens in our laboratory is performed with fastidious attention to the avoidance of any such cross-contamination. Second, no laboratory cross-contamination has ever been documented in other primate laboratories, including the NIH, even between infected and uninfected animals housed in the same or adjacent cages with daily intimate contact (P. Brown, personal communication). Third, the cerebral lesion profile is different from all the other prion diseases we have studied in this model19, with a correlation between cerebellar lesions (massive spongiform change of Purkinje cells, intense PrPres staining and reactive gliosis26) and ataxia. The iron deposits present in the globus pallidus are a non specific finding that have been reported previously in neurodegenerative diseases and aging27. Conversely, the thalamic lesion was reminiscent of a metabolic disease due to thiamine deficiency28 but blood thiamine levels were within normal limits (data not shown). The preferential distribution of spongiform change in cortex associated with a limited distribution in the brainstem is reminiscent of the lesion profile in MM2c and VV1 sCJD patients29, but interspecies comparison of lesion profiles should be interpreted with caution. It is of note that the same classical scrapie isolate induced TSE in C57Bl/6 mice with similar incubation periods and lesional profiles as a sample derived from a MM1 sCJD patient30.
We are therefore confident that the illness in this cynomolgus macaque represents a true transmission of a sheep c-scrapie isolate directly to an old-world monkey, which taxonomically resides in the primate subdivision (parvorder of catarrhini) that includes humans. With an homology of its PrP protein with humans of 96.4%31, cynomolgus macaque constitutes a highly relevant model for assessing zoonotic risk of prion diseases. Since our initial aim was to show the absence of transmission of scrapie to macaques in the worst-case scenario, we obtained materials from a flock of naturally-infected sheep, affecting animals with different genotypes32. This c-scrapie isolate exhibited complete transmission in ARQ/ARQ sheep (332 ± 56 days) and Tg338 transgenic mice expressing ovine VRQ/VRQ prion protein (220 ± 5 days) (O. Andreoletti, personal communication). From the standpoint of zoonotic risk, it is important to note that sheep with c-scrapie (including the isolate used in our study) have demonstrable infectivity throughout their lymphoreticular system early in the incubation period of the disease (3 months-old for all the lymphoid organs, and as early as 2 months-old in gut-associated lymph nodes)33. In addition, scrapie infectivity has been identified in blood34, milk35 and skeletal muscle36 from asymptomatic but scrapie infected small ruminants which implies a potential dietary exposure for consumers.
Two earlier studies have reported the occurrence of clinical TSE in cynomolgus macaques after exposures to scrapie isolates. In the first study, the “Compton” scrapie isolate (derived from an English sheep) and serially propagated for 9 passages in goats did not transmit TSE in cynomolgus macaque, rhesus macaque or chimpanzee within 7 years following intracerebral challenge1; conversely, after 8 supplementary passages in conventional mice, this “Compton” isolate induced TSE in a cynomolgus macaque 5 years after intracerebral challenge, but rhesus macaques and chimpanzee remained asymptomatic 8.5 years post-exposure8. However, multiple successive passages that are classically used to select laboratory-adapted prion strains can significantly modify the initial properties of a scrapie isolate, thus questioning the relevance of zoonotic potential for the initial sheep-derived isolate. The same isolate had also induced disease into squirrel monkeys (new-world monkey)9. A second historical observation reported that a cynomolgus macaque developed TSE 6 years post-inoculation with brain homogenate from a scrapie-infected Suffolk ewe (derived from USA), whereas a rhesus macaque and a chimpanzee exposed to the same inoculum remained healthy 9 years post-exposure1. This inoculum also induced TSE in squirrel monkeys after 4 passages in mice. Other scrapie transmission attempts in macaque failed but had more shorter periods of observation in comparison to the current study. Further, it is possible that there are differences in the zoonotic potential of different scrapie strains.
The most striking observation in our study is the extended incubation period of scrapie in the macaque model, which has several implications. Firstly, our observations constitute experimental evidence in favor of the zoonotic potential of c-scrapie, at least for this isolate that has been extensively studied32,33,34,35,36. The cross-species zoonotic ability of this isolate should be confirmed by performing duplicate intracerebral exposures and assessing the transmissibility by the oral route (a successful transmission of prion strains through the intracerebral route may not necessarily indicate the potential for oral transmission37). However, such confirmatory experiments may require more than one decade, which is hardly compatible with current general management and support of scientific projects; thus this study should be rather considered as a case report.
Secondly, transmission of c-BSE to primates occurred within 8 years post exposure for the lowest doses able to transmit the disease (the survival period after inoculation is inversely proportional to the initial amount of infectious inoculum). The occurrence of scrapie 10 years after exposure to a high dose (25 mg) of scrapie-infected sheep brain suggests that the macaque has a higher species barrier for sheep c-scrapie than c-BSE, although it is notable that previous studies based on in vitro conversion of PrP suggested that BSE and scrapie prions would have a similar conversion potential for human PrP38.
Thirdly, prion diseases typically have longer incubation periods after oral exposure than after intracerebral inoculations: since humans can develop Kuru 47 years after oral exposure39, an incubation time of several decades after oral exposure to scrapie would therefore be expected, leading the disease to occur in older adults, i.e. the peak age for cases considered to be sporadic disease, and making a distinction between scrapie-associated and truly sporadic disease extremely difficult to appreciate.
Fourthly, epidemiologic evidence is necessary to confirm the zoonotic potential of an animal disease suggested by experimental studies. A relatively short incubation period and a peculiar epidemiological situation (e.g., all the first vCJD cases occurring in the country with the most important ongoing c-BSE epizootic) led to a high degree of suspicion that c-BSE was the cause of vCJD. Sporadic CJD are considered spontaneous diseases with an almost stable and constant worldwide prevalence (0.5–2 cases per million inhabitants per year), and previous epidemiological studies were unable to draw a link between sCJD and classical scrapie6,7,40,41, even though external causes were hypothesized to explain the occurrence of some sCJD clusters42,43,44. However, extended incubation periods exceeding several decades would impair the predictive values of epidemiological surveillance for prion diseases, already weakened by a limited prevalence of prion diseases and the multiplicity of isolates gathered under the phenotypes of “scrapie” and “sporadic CJD”.
Fifthly, considering this 10 year-long incubation period, together with both laboratory and epidemiological evidence of decade or longer intervals between infection and clinical onset of disease, no premature conclusions should be drawn from negative transmission studies in cynomolgus macaques with less than a decade of observation, as in the aforementioned historical transmission studies of scrapie to primates1,8,9. Our observations and those of others45,46 to date are unable to provide definitive evidence regarding the zoonotic potential of CWD, atypical/Nor98 scrapie or H-type BSE. The extended incubation period of the scrapie-affected macaque in the current study also underscores the limitations of rodent models expressing human PrP for assessing the zoonotic potential of some prion diseases since their lifespan remains limited to approximately two years21,47,48. This point is illustrated by the fact that the recently reported transmission of scrapie to humanized mice was not associated with clinical signs for up to 750 days and occurred in an extreme minority of mice with only a marginal increase in attack rate upon second passage13. The low attack rate in these studies is certainly linked to the limited lifespan of mice compared to the very long periods of observation necessary to demonstrate the development of scrapie. Alternatively, one could estimate that a successful second passage is the result of strain adaptation to the species barrier, thus poorly relevant of the real zoonotic potential of the original scrapie isolate of sheep origin49. The development of scrapie in this primate after an incubation period compatible with its lifespan complements the study conducted in transgenic (humanized) mice; taken together these studies suggest that some isolates of sheep scrapie can promote misfolding of the human prion protein and that scrapie can develop within the lifespan of some primate species.
In addition to previous studies on scrapie transmission to primate1,8,9 and the recently published study on transgenic humanized mice13, our results constitute new evidence for recommending that the potential risk of scrapie for human health should not be dismissed. Indeed, human PrP transgenic mice and primates are the most relevant models for investigating the human transmission barrier. To what extent such models are informative for measuring the zoonotic potential of an animal TSE under field exposure conditions is unknown. During the past decades, many protective measures have been successfully implemented to protect cattle from the spread of c-BSE, and some of these measures have been extended to sheep and goats to protect from scrapie according to the principle of precaution. Since cases of c-BSE have greatly reduced in number, those protective measures are currently being challenged and relaxed in the absence of other known zoonotic animal prion disease. We recommend that risk managers should be aware of the long term potential risk to human health of at least certain scrapie isolates, notably for lymphotropic strains like the classical scrapie strain used in the current study. Relatively high amounts of infectivity in peripheral lymphoid organs in animals infected with these strains could lead to contamination of food products produced for human consumption. Efforts should also be maintained to further assess the zoonotic potential of other animal prion strains in long-term studies, notably lymphotropic strains with high prevalence like CWD, which is spreading across North America, and atypical/Nor98 scrapie (Nor98)50 that was first detected in the past two decades and now represents approximately half of all reported cases of prion diseases in small ruminants worldwide, including territories previously considered as scrapie free... Even if the prevailing view is that sporadic CJD is due to the spontaneous formation of CJD prions, it remains possible that its apparent sporadic nature may, at least in part, result from our limited capacity to identify an environmental origin.
Singeltary on Scrapie and human transmission way back, see;
1: J Neurol Neurosurg Psychiatry 1994 Jun;57(6):757-8
***> Transmission of Creutzfeldt-Jakob disease to a chimpanzee by electrodes contaminated during neurosurgery.
Gibbs CJ Jr, Asher DM, Kobrine A, Amyx HL, Sulima MP, Gajdusek DC.
Laboratory of Central Nervous System Studies, National Institute of
Neurological Disorders and Stroke, National Institutes of Health,
Bethesda, MD 20892.
Stereotactic multicontact electrodes used to probe the cerebral cortex of a middle aged woman with progressive dementia were previously implicated in the accidental transmission of Creutzfeldt-Jakob disease (CJD) to two younger patients. The diagnoses of CJD have been confirmed for all three cases. More than two years after their last use in humans, after three cleanings and repeated sterilisation in ethanol and formaldehyde vapour, the electrodes were implanted in the cortex of a chimpanzee. Eighteen months later the animal became ill with CJD. This finding serves to re-emphasise the potential danger posed by reuse of instruments contaminated with the agents of spongiform encephalopathies, even after scrupulous attempts to clean them.
PMID: 8006664 [PubMed - indexed for MEDLINE]
***> CONGRESSIONAL ABSTRACTS PRION CONFERENCE 2018
P69 Experimental transmission of CWD from white-tailed deer to co-housed reindeer
Mitchell G (1), Walther I (1), Staskevicius A (1), Soutyrine A (1), Balachandran A (1)
(1) National & OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada.
Chronic wasting disease (CWD) continues to be detected in wild and farmed cervid populations of North America, affecting predominantly white-tailed deer, mule deer and elk. Extensive herds of wild caribou exist in northern regions of Canada, although surveillance has not detected the presence of CWD in this population. Oral experimental transmission has demonstrated that reindeer, a species closely related to caribou, are susceptible to CWD. Recently, CWD was detected for the first time in Europe, in wild Norwegian reindeer, advancing the possibility that caribou in North America could also become infected. Given the potential overlap in habitat between wild CWD-infected cervids and wild caribou herds in Canada, we sought to investigate the horizontal transmissibility of CWD from white-tailed deer to reindeer.
Two white-tailed deer were orally inoculated with a brain homogenate prepared from a farmed Canadian white-tailed deer previously diagnosed with CWD. Two reindeer, with no history of exposure to CWD, were housed in the same enclosure as the white-tailed deer, 3.5 months after the deer were orally inoculated. The white-tailed deer developed clinical signs consistent with CWD beginning at 15.2 and 21 months post-inoculation (mpi), and were euthanized at 18.7 and 23.1 mpi, respectively. Confirmatory testing by immunohistochemistry (IHC) and western blot demonstrated widespread aggregates of pathological prion protein (PrPCWD) in the central nervous system and lymphoid tissues of both inoculated white-tailed deer. Both reindeer were subjected to recto-anal mucosal associated lymphoid tissue (RAMALT) biopsy at 20 months post-exposure (mpe) to the white-tailed deer. The biopsy from one reindeer contained PrPCWD confirmed by IHC. This reindeer displayed only subtle clinical evidence of disease prior to a rapid decline in condition requiring euthanasia at 22.5 mpe. Analysis of tissues from this reindeer by IHC revealed widespread PrPCWD deposition, predominantly in central nervous system and lymphoreticular tissues. Western blot molecular profiles were similar between both orally inoculated white-tailed deer and the CWD positive reindeer. Despite sharing the same enclosure, the other reindeer was RAMALT negative at 20 mpe, and PrPCWD was not detected in brainstem and lymphoid tissues following necropsy at 35 mpe. Sequencing of the prion protein gene from both reindeer revealed differences at several codons, which may have influenced susceptibility to infection.
Natural transmission of CWD occurs relatively efficiently amongst cervids, supporting the expanding geographic distribution of disease and the potential for transmission to previously naive populations. The efficient horizontal transmission of CWD from white-tailed deer to reindeer observed here highlights the potential for reindeer to become infected if exposed to other cervids or environments infected with CWD.
Infectious agent of sheep scrapie may persist in the environment for at least 16 years
Gudmundur Georgsson,1 Sigurdur Sigurdarson2 and Paul Brown3
Correspondence
1 Institute for Experimental Pathology, University of Iceland, Keldur v/vesturlandsveg, IS-112 Reykjavı´k, Iceland
2 Laboratory of the Chief Veterinary Officer, Keldur, Iceland
3 Bethesda, Maryland, USA
Received 7 March 2006 Accepted 6 August 2006
In 1978, a rigorous programme was implemented to stop the spread of, and subsequently eradicate, sheep scrapie in Iceland. Affected flocks were culled, premises were disinfected and, after 2–3 years, restocked with lambs from scrapie-free areas. Between 1978 and 2004, scrapie recurred on 33 farms. Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded. Of special interest was one farm with a small, completely self-contained flock where scrapie recurred 18 years after culling, 2 years after some lambs had been housed in an old sheephouse that had never been disinfected. Epidemiological investigation established with near certitude that the disease had not been introduced from the outside and it is concluded that the agent may have persisted in the old sheep-house for at least 16 years.
21 YEARS!
***>>>Nine of these recurrences occurred 14–21 years after culling, apparently as the result of environmental contamination, but outside entry could not always be absolutely excluded...tss
***> CONGRESSIONAL ABSTRACTS PRION CONFERENCE 2018
P69 Experimental transmission of CWD from white-tailed deer to co-housed reindeer
Mitchell G (1), Walther I (1), Staskevicius A (1), Soutyrine A (1), Balachandran A (1)
(1) National & OIE Reference Laboratory for Scrapie and CWD, Canadian Food Inspection Agency, Ottawa, Ontario, Canada.
Chronic wasting disease (CWD) continues to be detected in wild and farmed cervid populations of North America, affecting predominantly white-tailed deer, mule deer and elk. Extensive herds of wild caribou exist in northern regions of Canada, although surveillance has not detected the presence of CWD in this population. Oral experimental transmission has demonstrated that reindeer, a species closely related to caribou, are susceptible to CWD. Recently, CWD was detected for the first time in Europe, in wild Norwegian reindeer, advancing the possibility that caribou in North America could also become infected. Given the potential overlap in habitat between wild CWD-infected cervids and wild caribou herds in Canada, we sought to investigate the horizontal transmissibility of CWD from white-tailed deer to reindeer.
Two white-tailed deer were orally inoculated with a brain homogenate prepared from a farmed Canadian white-tailed deer previously diagnosed with CWD. Two reindeer, with no history of exposure to CWD, were housed in the same enclosure as the white-tailed deer, 3.5 months after the deer were orally inoculated. The white-tailed deer developed clinical signs consistent with CWD beginning at 15.2 and 21 months post-inoculation (mpi), and were euthanized at 18.7 and 23.1 mpi, respectively. Confirmatory testing by immunohistochemistry (IHC) and western blot demonstrated widespread aggregates of pathological prion protein (PrPCWD) in the central nervous system and lymphoid tissues of both inoculated white-tailed deer. Both reindeer were subjected to recto-anal mucosal associated lymphoid tissue (RAMALT) biopsy at 20 months post-exposure (mpe) to the white-tailed deer. The biopsy from one reindeer contained PrPCWD confirmed by IHC. This reindeer displayed only subtle clinical evidence of disease prior to a rapid decline in condition requiring euthanasia at 22.5 mpe. Analysis of tissues from this reindeer by IHC revealed widespread PrPCWD deposition, predominantly in central nervous system and lymphoreticular tissues. Western blot molecular profiles were similar between both orally inoculated white-tailed deer and the CWD positive reindeer. Despite sharing the same enclosure, the other reindeer was RAMALT negative at 20 mpe, and PrPCWD was not detected in brainstem and lymphoid tissues following necropsy at 35 mpe. Sequencing of the prion protein gene from both reindeer revealed differences at several codons, which may have influenced susceptibility to infection.
Natural transmission of CWD occurs relatively efficiently amongst cervids, supporting the expanding geographic distribution of disease and the potential for transmission to previously naive populations. The efficient horizontal transmission of CWD from white-tailed deer to reindeer observed here highlights the potential for reindeer to become infected if exposed to other cervids or environments infected with CWD.
TITLE: PATHOLOGICAL FEATURES OF CHRONIC WASTING DISEASE IN REINDEER AND DEMONSTRATION OF HORIZONTAL TRANSMISSION
*** DECEMBER 2016 CDC EMERGING INFECTIOUS DISEASE JOURNAL CWD HORIZONTAL TRANSMISSION
SEE;
Back around 2000, 2001, or so, I was corresponding with officials abroad during the bse inquiry, passing info back and forth, and some officials from here inside USDA aphis FSIS et al. In fact helped me get into the USA 50 state emergency BSE conference call way back. That one was a doozy. But I always remember what “deep throat” I never knew who they were, but I never forgot;
Some unofficial information from a source on the inside looking out -
Confidential!!!!
As early as 1992-3 there had been long studies conducted on small pastures containing scrapie infected sheep at the sheep research station associated with the Neuropathogenesis Unit in Edinburgh, Scotland. Whether these are documented...I don't know. But personal recounts both heard and recorded in a daily journal indicate that leaving the pastures free and replacing the topsoil completely at least 2 feet of thickness each year for SEVEN years....and then when very clean (proven scrapie free) sheep were placed on these small pastures.... the new sheep also broke out with scrapie and passed it to offspring. I am not sure that TSE contaminated ground could ever be free of the agent!! A very frightening revelation!!!
---end personal email---end...tss
Infectivity surviving ashing to 600*C is (in my opinion) degradable but infective. based on Bown & Gajdusek, (1991), landfill and burial may be assumed to have a reduction factor of 98% (i.e. a factor of 50) over 3 years. CJD-infected brain-tissue remained infectious after storing at room-temperature for 22 months (Tateishi et al, 1988). Scrapie agent is known to remain viable after at least 30 months of desiccation (Wilson et al, 1950). and pastures that had been grazed by scrapie-infected sheep still appeared to be contaminated with scrapie agent three years after they were last occupied by sheep (Palsson, 1979).
Dr. Paul Brown Scrapie Soil Test BSE Inquiry Document
Using in vitro Prion replication for high sensitive detection of prions and prionlike proteins and for understanding mechanisms of transmission.
Claudio Soto Mitchell Center for Alzheimer's diseases and related Brain disorders, Department of Neurology, University of Texas Medical School at Houston.
Prion and prion-like proteins are misfolded protein aggregates with the ability to selfpropagate to spread disease between cells, organs and in some cases across individuals. I n T r a n s m i s s i b l e s p o n g i f o r m encephalopathies (TSEs), prions are mostly composed by a misfolded form of the prion protein (PrPSc), which propagates by transmitting its misfolding to the normal prion protein (PrPC). The availability of a procedure to replicate prions in the laboratory may be important to study the mechanism of prion and prion-like spreading and to develop high sensitive detection of small quantities of misfolded proteins in biological fluids, tissues and environmental samples. Protein Misfolding Cyclic Amplification (PMCA) is a simple, fast and efficient methodology to mimic prion replication in the test tube. PMCA is a platform technology that may enable amplification of any prion-like misfolded protein aggregating through a seeding/nucleation process. In TSEs, PMCA is able to detect the equivalent of one single molecule of infectious PrPSc and propagate prions that maintain high infectivity, strain properties and species specificity. Using PMCA we have been able to detect PrPSc in blood and urine of experimentally infected animals and humans affected by vCJD with high sensitivity and specificity. Recently, we have expanded the principles of PMCA to amplify amyloid-beta (Aβ) and alphasynuclein (α-syn) aggregates implicated in Alzheimer's and Parkinson's diseases, respectively. Experiments are ongoing to study the utility of this technology to detect Aβ and α-syn aggregates in samples of CSF and blood from patients affected by these diseases.
=========================
***>>> Recently, we have been using PMCA to study the role of environmental prion contamination on the horizontal spreading of TSEs. These experiments have focused on the study of the interaction of prions with plants and environmentally relevant surfaces. Our results show that plants (both leaves and roots) bind tightly to prions present in brain extracts and excreta (urine and feces) and retain even small quantities of PrPSc for long periods of time. Strikingly, ingestion of prioncontaminated leaves and roots produced disease with a 100% attack rate and an incubation period not substantially longer than feeding animals directly with scrapie brain homogenate. Furthermore, plants can uptake prions from contaminated soil and transport them to different parts of the plant tissue (stem and leaves). Similarly, prions bind tightly to a variety of environmentally relevant surfaces, including stones, wood, metals, plastic, glass, cement, etc. Prion contaminated surfaces efficiently transmit prion disease when these materials were directly injected into the brain of animals and strikingly when the contaminated surfaces were just placed in the animal cage. These findings demonstrate that environmental materials can efficiently bind infectious prions and act as carriers of infectivity, suggesting that they may play an important role in the horizontal transmission of the disease.
========================
Since its invention 13 years ago, PMCA has helped to answer fundamental questions of prion propagation and has broad applications in research areas including the food industry, blood bank safety and human and veterinary disease diagnosis.
New studies on the heat resistance of hamster-adapted scrapie agent: Threshold survival after ashing at 600°C suggests an inorganic template of replication
Prion Infected Meat-and-Bone Meal Is Still Infectious after Biodiesel Production
Detection of protease-resistant cervid prion protein in water from a CWD-endemic area
A Quantitative Assessment of the Amount of Prion Diverted to Category 1 Materials and Wastewater During Processing
Rapid assessment of bovine spongiform encephalopathy prion inactivation by heat treatment in yellow grease produced in the industrial manufacturing process of meat and bone meals
PPo4-4:
Survival and Limited Spread of TSE Infectivity after Burial
Discussion Classical scrapie is an environmentally transmissible disease because it has been reported in naïve, supposedly previously unexposed sheep placed in pastures formerly occupied by scrapie-infected sheep (4, 19, 20).
Although the vector for disease transmission is not known, soil is likely to be an important reservoir for prions (2) where – based on studies in rodents – prions can adhere to minerals as a biologically active form (21) and remain infectious for more than 2 years (22).
Similarly, chronic wasting disease (CWD) has re-occurred in mule deer housed in paddocks used by infected deer 2 years earlier, which was assumed to be through foraging and soil consumption (23).
Our study suggested that the risk of acquiring scrapie infection was greater through exposure to contaminated wooden, plastic, and metal surfaces via water or food troughs, fencing, and hurdles than through grazing.
Drinking from a water trough used by the scrapie flock was sufficient to cause infection in sheep in a clean building.
Exposure to fences and other objects used for rubbing also led to infection, which supported the hypothesis that skin may be a vector for disease transmission (9).
The risk of these objects to cause infection was further demonstrated when 87% of 23 sheep presented with PrPSc in lymphoid tissue after grazing on one of the paddocks, which contained metal hurdles, a metal lamb creep and a water trough in contact with the scrapie flock up to 8 weeks earlier, whereas no infection had been demonstrated previously in sheep grazing on this paddock, when equipped with new fencing and field furniture.
When the contaminated furniture and fencing were removed, the infection rate dropped significantly to 8% of 12 sheep, with soil of the paddock as the most likely source of infection caused by shedding of prions from the scrapie-infected sheep in this paddock up to a week earlier.
This study also indicated that the level of contamination of field furniture sufficient to cause infection was dependent on two factors: stage of incubation period and time of last use by scrapie-infected sheep.
Drinking from a water trough that had been used by scrapie sheep in the predominantly pre-clinical phase did not appear to cause infection, whereas infection was shown in sheep drinking from the water trough used by scrapie sheep in the later stage of the disease.
It is possible that contamination occurred through shedding of prions in saliva, which may have contaminated the surface of the water trough and subsequently the water when it was refilled.
Contamination appeared to be sufficient to cause infection only if the trough was in contact with sheep that included clinical cases.
Indeed, there is an increased risk of bodily fluid infectivity with disease progression in scrapie (24) and CWD (25) based on PrPSc detection by sPMCA.
Although ultraviolet light and heat under natural conditions do not inactivate prions (26), furniture in contact with the scrapie flock, which was assumed to be sufficiently contaminated to cause infection, did not act as vector for disease if not used for 18 months, which suggest that the weathering process alone was sufficient to inactivate prions.
PrPSc detection by sPMCA is increasingly used as a surrogate for infectivity measurements by bioassay in sheep or mice.
In this reported study, however, the levels of PrPSc present in the environment were below the limit of detection of the sPMCA method, yet were still sufficient to cause infection of in-contact animals.
In the present study, the outdoor objects were removed from the infected flock 8 weeks prior to sampling and were positive by sPMCA at very low levels (2 out of 37 reactions).
As this sPMCA assay also yielded 2 positive reactions out of 139 in samples from the scrapie-free farm, the sPMCA assay could not detect PrPSc on any of the objects above the background of the assay.
False positive reactions with sPMCA at a low frequency associated with de novo formation of infectious prions have been reported (27, 28).
This is in contrast to our previous study where we demonstrated that outdoor objects that had been in contact with the scrapie-infected flock up to 20 days prior to sampling harbored PrPSc that was detectable by sPMCA analysis [4 out of 15 reactions (12)] and was significantly more positive by the assay compared to analogous samples from the scrapie-free farm.
This discrepancy could be due to the use of a different sPMCA substrate between the studies that may alter the efficiency of amplification of the environmental PrPSc.
In addition, the present study had a longer timeframe between the objects being in contact with the infected flock and sampling, which may affect the levels of extractable PrPSc.
Alternatively, there may be potentially patchy contamination of this furniture with PrPSc, which may have been missed by swabbing.
The failure of sPMCA to detect CWD-associated PrP in saliva from clinically affected deer despite confirmation of infectivity in saliva-inoculated transgenic mice was associated with as yet unidentified inhibitors in saliva (29), and it is possible that the sensitivity of sPMCA is affected by other substances in the tested material.
In addition, sampling of amplifiable PrPSc and subsequent detection by sPMCA may be more difficult from furniture exposed to weather, which is supported by the observation that PrPSc was detected by sPMCA more frequently in indoor than outdoor furniture (12).
A recent experimental study has demonstrated that repeated cycles of drying and wetting of prion-contaminated soil, equivalent to what is expected under natural weathering conditions, could reduce PMCA amplification efficiency and extend the incubation period in hamsters inoculated with soil samples (30).
This seems to apply also to this study even though the reduction in infectivity was more dramatic in the sPMCA assays than in the sheep model.
Sheep were not kept until clinical end-point, which would have enabled us to compare incubation periods, but the lack of infection in sheep exposed to furniture that had not been in contact with scrapie sheep for a longer time period supports the hypothesis that prion degradation and subsequent loss of infectivity occurs even under natural conditions.
In conclusion, the results in the current study indicate that removal of furniture that had been in contact with scrapie-infected animals should be recommended, particularly since cleaning and decontamination may not effectively remove scrapie infectivity (31), even though infectivity declines considerably if the pasture and the field furniture have not been in contact with scrapie-infected sheep for several months. As sPMCA failed to detect PrPSc in furniture that was subjected to weathering, even though exposure led to infection in sheep, this method may not always be reliable in predicting the risk of scrapie infection through environmental contamination.
These results suggest that the VRQ/VRQ sheep model may be more sensitive than sPMCA for the detection of environmentally associated scrapie, and suggest that extremely low levels of scrapie contamination are able to cause infection in susceptible sheep genotypes.
Keywords: classical scrapie, prion, transmissible spongiform encephalopathy, sheep, field furniture, reservoir, serial protein misfolding cyclic amplification
Wednesday, December 16, 2015
*** Objects in contact with classical scrapie sheep act as a reservoir for scrapie transmission ***
***> 2018 URGENT DATA <***
THURSDAY, OCTOBER 25, 2018
***> Norway New additional requirements for imports of hay and straw for animal feed from countries outside the EEA due to CWD TSE Prion
JUST OUT CDC;
Tuesday, November 20, 2018
Eyes of CJD patients show evidence of prions Finding could help early diagnosis, raise concern for eye exams and transplants.
Singeltary 1999
***> THE EYES HAVE IT, CJD, AND THEY COULD BE STEALING THEM FROM YOUR LOVED ONE!...year 1999
i said that 20 years ago about this very thing. but did anyone listen...no!
prepare for the storm...terry
year 1999 to 2000
Subject: RE-The Eyes Have It (cjd) and they could be stealing them from your loved one... "pay back time"
Date: Sat, 16 Sep 2000 10:04:26 -0700
From: "Terry S. Singeltary Sr."
Reply-To: Bovine Spongiform Encephalopathy
To: BSE-L@uni-karlsruhe.de
######### Bovine Spongiform Encephalopathy #########
Greetings List Members,
I hate to keep kicking a madcow, but this still is very disturbing to me. Not only for the recipient of the cornea's, but as well, for the people whom would be operated on, using the same tools that were used to put those stolen cornea's in the recipient with. No history of this donor or his family (re-ffi), or anything would be known, using stolen organs and or tissue's. I just think this is not only wrong, but very dangerous to a great many other people, as this is one of the most infectious tissues of TSE's. It seems that this practice of stealing organ/tissue happens more than we think. Anyway, the family of the victim which had their cornea's stolen, are now suing. In the example I used with my Mother, if 3 months before, she would have been in a catastrophic accident (car wreck, whatever), no autopsy (for whatever reason), no family (for whatever reason), she lay in the morgue, and after 4 hours, they come steal the cornea's, lot of people could have been infected, just because of lack of medical history of donor/family. It may be hypothetical, but very real. We need to stop the spread of this disease.
kind regards, Terry S. Singeltary Sr., Bacliff, Texas USA
===========================================
Previous story--
Cadaver corneal transplants -- without family permission...
Cadaver corneal transplants -- without family permission Houston, Texas channel 11 news 28 Nov 99
Reported by Terry S. Singeltary Sr.son of CJD victim
"It was a story about how the Lions eye bank were harvesting corneas from victims in the Morgue, without their consent. Under Texas law, this appears to be legal (remember Texas has the Veggie liable law). Even if Family says no, this appears to happen, from what the news story said.
They said the only way to prevent this, is to fill out a form, stating not to have this done. So if you don't fill out the form, they can do this. How many people don't know about the form?
This is not only disgusting and appalling, it could be highly infectious. Without proper background checking of the donors, on their physical history, checking on past dementia, and/or family history, some of these unfortunate victims, could be passing a human TSE.
Response Jill Spitler Clevelland Eye Bank:
"No, we are not stealing.........Yes, you do have such a law in the state of Texas, but not all your state Eye Banks utilize the law. The Eye Bank that you're speaking of is only one of 43 certified Eye Bank throughout the USA.
And there are measure taken per the Medical Standards of the Eye Bank Association of America, the certifying body for eye banks and per FDA regulations to address those concerns that you speak of.
I would suggest that those interested/concern with transplant contact their local agencies. The Eye Bank Association of America has a web. site . Further if anyone has problems contacting or finding out about their local organization(s), call me or e-mail me I would be glad to help. My e-mail address is jill@clevelandeyebank.org"
Terry Singeltary responds:
"Explain this to the family in Houston who went to their loved ones funeral, only to find out that the loved one that was in the casket, had their corneas removed without their permission, without the consent of the victim or it's family. They would not have known it, only for the funny look the victim had. So, they questioned, only to find out, the corneas, had in fact, been removed without consent.
I call that stealing, regardless what the law states. This type of legal grave robbing is not a logical thing to do without knowing any type of background of the victims medical past, which really will not prove anything due to the incubation period. Eye tissue being potentially a highly infective source, there are risks here.
Should they not at least know of the potential ramifications of TSE's (the person receiving the corneas)?
Should there not be some sort of screening?
Should there be some sort of moral issue here?
If this is the case, and in fact, they can come take your corneas, without your consent, then what will they start taking next, without your consent?
Lets look at a hypothetical situation:
What would happen if my Mom (DOD 12-14-97 hvCJD) would have gotten into a car wreck and died, before the symptoms of CJD appeared. Not much money, so there was no autopsy. What would have happened to that recipient of those infecting corneas?"
Comment (webmaster): Actual transmission of CJD by means of corneal transplant may or may not be rare. The incidence of infectivity in older people could be fairly high; this is not to be confused with the lower incidence of symptomatic (clinical) CJD. It is very unlikely that familial CJD would have been diagnosed in earlier generations; however, without interviewing the family even known kindreds would not be excluded.
In blood donation, a much stricter policy is followed, even though corneal transplant may be far more dangerous (being a direct link to the brain and not going through purification steps).
Since highly sensitive tests for pre-clinical CJD are now available, it would make sense to screen corneas for CJD, just as they are screened for AIDS, hepatitus, and a host of other conditions.
Eye procedure raises CJD concerns
BySTEVE MITCHELL, Medical Correspondent
WASHINGTON, Nov. 18 (UPI) -- A New York man who died from a rare brain disorder similar to mad cow disease in May underwent an eye procedure prior to his death that raises concerns about the possibility of transmitting the fatal disease to others, United Press International has learned.
The development comes on the heels of the announcement Thursday by U.S. Department of Agriculture officials of a possible second case of mad cow disease in U.S. herds.
Richard Da Silva, 58, of Orange County, N.Y., died from Creutzfeldt Jakob disease, an incurable brain-wasting illness that strikes about one person per million.
Richard's wife Ann Marie Da Silva told UPI he underwent a check for the eye disease glaucoma in 2003, approximately a year before his death. The procedure involves the use of a tonometer, which contacts the cornea -- an eye tissue that can contain prions, the infectious agent thought to cause CJD.
Ann Marie's concern is that others who had the tonometer used on them could have gotten infected.
A 2003 study by British researchers suggests her concerns may be justified. A team led by J.W. Ironside from the National Creutzfeldt-Jakob Disease Surveillance Unit at the University of Edinburgh examined tonometer heads and found they can retain cornea tissue that could infect other people -- even after cleaning and decontaminating the instrument.
"Retained corneal epithelial cells, following the standard decontamination routine of tonometer prisms, may represent potential prion infectivity," the researchers wrote in the British Journal of Ophthalmology last year. "Once the infectious agent is on the cornea, it could theoretically infect the brain."
Prions, misfolded proteins thought to be the cause of mad cow, CJD and similar diseases, are notoriously difficult to destroy and are capable of withstanding most sterilization procedures.
Laura Manuelidis, an expert on these diseases and section chief of surgery in the neuropathology department at Yale University, agreed with the British researchers that tonometers represent a potential risk of passing CJD to other people.
Manuelidis told UPI she has been voicing her concern about the risks of corneas since 1977 when her own study, published in the New England Journal of Medicine, showed the eye tissue, if infected, could transmit CJD.
At the time the procedure was done on Richard Da Silva, about a year before he died, she said it was "absolutely" possible he was infectious.
The CJD Incidents Panel, a body of experts set up by the U.K. Department of Health, noted in a 2001 report that procedures involving the cornea are considered medium risk for transmitting CJD. The first two patients who have a contaminated eye instrument used on them have the highest risk of contracting the disease, the panel said.
In 1999, the U.K. Department of Health banned opticians from reusing equipment that came in contact with patients' eyes out of concern it could result in the transmission of variant CJD, the form of the disease humans can contract from consuming infected beef products.
Richard Da Silva was associated with a cluster of five other cases of CJD in southern New York that raised concerns about vCJD.
None of the cases have been determined to stem from mad cow disease, but concerns about the cattle illness in the United States could increase in light of the USDA announcement Thursday that a cow tested positive on initial tests for the disease. If confirmed, this would be the second U.S. case of the illness; the first was detected in a Washington cow last December. The USDA said the suspect animal disclosed Thursday did not enter the food chain. The USDA did not release further details about the cow, but said results from further lab tests to confirm the initial tests were expected within seven days.
Ann Marie Da Silva said she informed the New York Health Department and later the eye doctor who performed the procedure about her husband's illness and her concerns about the risk of transmitting CJD via the tonometer.
The optometrist -- whom she declined to name because she did not want to jeopardize his career -- "didn't even know what this disease was," she said.
"He said the health department never called him and I called them (the health department) back and they didn't seem concerned about it," she added. "I just kept getting angrier and angrier when I felt I was being dismissed."
She said the state health department "seems to have an attitude of don't ask, don't tell" about CJD.
"There's a stigma attached to it," she said. "Is it because they're so afraid the public will panic? I don't know, but I don't think that the answer is to push things under the rug."
New York State Department of Health spokeswoman Claire Pospisil told UPI she would look into whether the agency was concerned about the possibility of transmitting CJD via tonometers, but she had not called back prior to story publication.
Disposable tonometers are readily available and could avoid the risk of transmitting the disease, Ironside and colleagues noted in their study. Ann Marie Da Silva said she asked the optometrist whether he used disposable tonometers and "he said 'No, it's a reusable one.'"
Ironside's team also noted other ophthalmic instruments come into contact with the cornea and could represent a source of infection as they are either difficult to decontaminate or cannot withstand the harsh procedures necessary to inactivate prions. These include corneal burrs, diagnostic and therapeutic contact lenses and other coated lenses.
Terry Singletary, whose mother died from a type of CJD called Heidenhain Variant, told UPI health officials were not doing enough to prevent people from being infected by contaminated medical equipment.
"They've got to start taking this disease seriously and they simply aren't doing it," said Singletary, who is a member of CJD Watch and CJD Voice -- advocacy groups for CJD patients and their families.
U.S. Centers for Disease Control and Prevention spokeswoman Christine Pearson did not return a phone call from UPI seeking comment. The agency's Web site states the eye is one of three tissues, along with the brain and spinal cord, that are considered to have "high infectivity."
The Web site said more than 250 people worldwide have contracted CJD through contaminated surgical instruments and tissue transplants. This includes as many as four who were infected by corneal grafts. The agency noted no such cases have been reported since 1976, when sterilization procedures were instituted in healthcare facilities.
Ironside and colleagues noted in their study, however, many disinfection procedures used on optical instruments, such as tonometers, fail. They wrote their finding of cornea tissue on tonometers indicates that "no current cleaning and disinfection strategy is fully effective."
Singletary said CDC's assertion that no CJD cases from infected equipment or tissues have been detected since 1976 is misleading.
"They have absolutely no idea" whether any cases have occurred in this manner, he said, because CJD cases often aren't investigated and the agency has not required physicians nationwide report all cases of CJD.
"There's no national surveillance unit for CJD in the United States; people are dying who aren't autopsied, the CDC has no way of knowing" whether people have been infected via infected equipment or tissues, he said.
Ann Marie Da Silva said she has contacted several members of her state's congressional delegation about her concerns, including Rep. Sue Kelly, R-N.Y., and Sen. Charles Schumer, D-N.Y.
"Basically, what I want is to be a positive force in this, but I also want more of a dialogue going on with the public and the health department," she said.
Friday, December 04, 2009
New guidance on decontamination of trial contact lenses and other contact devices has been revealed for CJD AND vCJD
SUNDAY, JANUARY 17, 2016
Of Grave Concern Heidenhain Variant Creutzfeldt Jakob Disease
TUESDAY, NOVEMBER 20, 2018
CDC Eyes of CJD patients show evidence of prions concerns for iatrogenic transmission
MONDAY, NOVEMBER 19, 2018
Benefit cuts hit mad cow disease sufferer A girl born severely disabled from vCJD may lose her home under universal credit
2006-2007
HUMAN and ANIMAL TSE Classifications i.e. mad cow disease and the UKBSEnvCJD only theory
TSEs have been rampant in the USA for decades in many species, and they all have been rendered and fed back to animals for human/animal consumption.
I propose that the current diagnostic criteria for human TSEs only enhances and helps the spreading of human TSE from the continued belief of the UKBSEnvCJD only theory in 2007.
With all the science to date refuting it, to continue to validate this myth, will only spread this TSE agent through a multitude of potential routes and sources i.e. consumption, surgical, blood, medical, cosmetics etc.
I propose as with Aguzzi, Asante, Collinge, Caughey, Deslys, Dormont, Gibbs, Ironside, Manuelidis, Marsh, et al and many more, that the world of TSE Transmissible Spongiform Encephalopathy is far from an exact science, but there is enough proven science to date that this myth should be put to rest once and for all, and that we move forward with a new classification for human and animal TSE that would properly identify the infected species, the source species, and then the route.
This would further have to be broken down to strain of species and then the route of transmission would further have to be broken down.
Accumulation and Transmission are key to the threshold from subclinical to clinical disease, and of that, I even believe that physical and or blunt trauma may play a role of onset of clinical symptoms in some cases, but key to all this, is to stop the amplification and transmission of this agent, the spreading of, no matter what strain.
BUT, to continue with this myth that the U.K. strain of BSE one strain in cows, and the nv/v CJD, one strain in humans, and that all the rest of human TSE is one single strain i.e. sporadic CJD (when to date there are 6 different phenotypes of sCJD), and that no other animal TSE transmits to humans, to continue with this masquerade will only continue to spread, expose, and kill, who knows how many more in the years and decades to come.
ONE was enough for me, My Mom, hvCJD, DOD 12/14/97 confirmed, which is nothing more than another mans name added to CJD, like CJD itself, Jakob and Creutzfeldt, or Gerstmann-Straussler-Scheinker syndrome, just another CJD or human TSE, named after another human.
WE are only kidding ourselves with the current diagnostic criteria for human and animal TSE, especially differentiating between the nvCJD vs the sporadic CJD strains and then the GSS strains and also the FFI fatal familial insomnia strains or the ones that mimics one or the other of those TSE?
Tissue infectivity and strain typing of the many variants of the human and animal TSEs are paramount in all variants of all TSE.
There must be a proper classification that will differentiate between all these human TSE in order to do this.
With the CDI and other more sensitive testing coming about, I only hope that my proposal will some day be taken seriously.
My name is Terry S. Singeltary Sr. and I am no scientist, no doctor and have no PhDs, but have been independently researching human and animal TSEs since the death of my Mother to the Heidenhain Variant of Creutzfeldt Jakob Disease on December 14, 1997 'confirmed'.
...END
Diagnosis and Reporting of Creutzfeldt-Jakob Disease
Singeltary, Sr et al. JAMA.2001; 285: 733-734. Vol. 285 No. 6, February 14, 2001 JAMA Diagnosis and Reporting of Creutzfeldt-Jakob Disease
To the Editor:
In their Research Letter, Dr Gibbons and colleagues1 reported that the annual US death rate due to Creutzfeldt-Jakob disease (CJD) has been stable since 1985. These estimates, however, are based only on reported cases, and do not include misdiagnosed or preclinical cases. It seems to me that misdiagnosis alone would drastically change these figures. An unknown number of persons with a diagnosis of Alzheimer disease in fact may have CJD, although only a small number of these patients receive the postmortem examination necessary to make this diagnosis. Furthermore, only a few states have made CJD reportable. Human and animal transmissible spongiform encephalopathies should be reportable nationwide and internationally.
Terry S. Singeltary, Sr Bacliff, Tex
1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Creutzfeldt-Jakob disease in the United States: 1979-1998. JAMA. 2000;284:2322-2323.
Diagnosis and Reporting of Creutzfeldt-Jakob Disease
Singeltary, Sr et al. JAMA.2001; 285: 733-734.
BRITISH MEDICAL JOURNAL
BMJ
U.S. Scientist should be concerned with a CJD epidemic in the U.S., as well....
02 January 2000
Terry S Singeltary
retired
US scientists develop a possible test for BSE
Rapid responses Response
Re: vCJD in the USA * BSE in U.S.
15 November 1999
Terry S Singeltary
NA
medically retired
January 28, 2003; 60 (2) VIEWS & REVIEWS
Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States
Ermias D. Belay, Ryan A. Maddox, Pierluigi Gambetti, Lawrence B. Schonberger
Abstract
Transmissible spongiform encephalopathies (TSEs) attracted increased attention in the mid-1980s because of the emergence among UK cattle of bovine spongiform encephalopathy (BSE), which has been shown to be transmitted to humans, causing a variant form of Creutzfeldt-Jakob disease (vCJD). The BSE outbreak has been reported in 19 European countries, Israel, and Japan, and human cases have so far been identified in four European countries, and more recently in a Canadian resident and a US resident who each lived in Britain during the BSE outbreak. To monitor the occurrence of emerging forms of CJD, such as vCJD, in the United States, the Centers for Disease Control and Prevention has been conducting surveillance for human TSEs through several mechanisms, including the establishment of the National Prion Disease Pathology Surveillance Center. Physicians are encouraged to maintain a high index of suspicion for vCJD and use the free services of the pathology center to assess the neuropathology of clinically diagnosed and suspected cases of CJD or other TSEs.
Received May 7, 2002. Accepted August 28, 2002.
RE-Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States
Terry S. Singeltary, retired (medically)
Published March 26, 2003
26 March 2003
Terry S. Singeltary, retired (medically) CJD WATCH
I lost my mother to hvCJD (Heidenhain Variant CJD). I would like to comment on the CDC's attempts to monitor the occurrence of emerging forms of CJD. Asante, Collinge et al [1] have reported that BSE transmission to the 129-methionine genotype can lead to an alternate phenotype that is indistinguishable from type 2 PrPSc, the commonest sporadic CJD. However, CJD and all human TSEs are not reportable nationally. CJD and all human TSEs must be made reportable in every state and internationally. I hope that the CDC does not continue to expect us to still believe that the 85%+ of all CJD cases which are sporadic are all spontaneous, without route/source. We have many TSEs in the USA in both animal and man. CWD in deer/elk is spreading rapidly and CWD does transmit to mink, ferret, cattle, and squirrel monkey by intracerebral inoculation. With the known incubation periods in other TSEs, oral transmission studies of CWD may take much longer. Every victim/family of CJD/TSEs should be asked about route and source of this agent. To prolong this will only spread the agent and needlessly expose others. In light of the findings of Asante and Collinge et al, there should be drastic measures to safeguard the medical and surgical arena from sporadic CJDs and all human TSEs. I only ponder how many sporadic CJDs in the USA are type 2 PrPSc?
Reply to Singletary Ryan A. Maddox, MPH Other Contributors: Published March 26, 2003
Mr. Singletary raises several issues related to current Creutzfeldt- Jakob disease (CJD) surveillance activities. Although CJD is not a notifiable disease in most states, its unique characteristics, particularly its invariably fatal outcome within usually a year of onset, make routine mortality surveillance a useful surrogate for ongoing CJD surveillance.[1] In addition, because CJD is least accurately diagnosed early in the course of illness, notifiable-disease surveillance could be less accurate than, if not duplicative of, current mortality surveillance.[1] However, in states where making CJD officially notifiable would meaningfully facilitate the collection of data to monitor for variant CJD (vCJD) or other emerging prion diseases, CDC encourages the designation of CJD as a notifiable disease.[1] Moreover, CDC encourages physicians to report any diagnosed or suspected CJD cases that may be of special public health importance (e.g., vCJD, iatrogenic CJD, unusual CJD clusters).
As noted in our article, strong evidence is lacking for a causal link between chronic wasting disease (CWD) of deer and elk and human disease,[2] but only limited data seeking such evidence exist. Overall, the previously published case-control studies that have evaluated environmental sources of infection for sporadic CJD have not consistently identified strong evidence for a common risk factor.[3] However, the power of a case-control study to detect a rare cause of CJD is limited, particularly given the relatively small number of subjects generally involved and its long incubation period, which may last for decades. Because only a very small proportion of the US population has been exposed to CWD, a targeted surveillance and investigation of unusual cases or case clusters of prion diseases among persons at increased risk of exposure to CWD is a more efficient approach to detecting the possible transmission of CWD to humans. In collaboration with appropriate local and state health departments and the National Prion Disease Pathology Surveillance Center, CDC is facilitating or conducting such surveillance and case- investigations, including related laboratory studies to characterize CJD and CWD prions.
Mr. Singletary also expresses concern over a recent publication by Asante and colleagues indicating the possibility that some sporadic CJD cases may be attributable to bovine spongiform encephalopathy (BSE).[4] The authors reported that transgenic mice expressing human prion protein homozygous for methionine at codon 129, when inoculated with BSE prions, developed a molecular phenotype consistent with a subtype of sporadic CJD. Although the authors implied that BSE might cause a sporadic CJD-like illness among persons homozygous for methionine, the results of their research with mice do not necessarily directly apply to the transmission of BSE to humans. If BSE causes a sporadic CJD-like illness in humans, an increase in sporadic CJD cases would be expected to first occur in the United Kingdom, where the vast majority of vCJD cases have been reported. In the United Kingdom during 1997 through 2002, however, the overall average annual mortality rate for sporadic CJD was not elevated; it was about 1 case per million population per year. In addition, during this most recent 6-year period following the first published description of vCJD in 1996, there was no increasing trend in the reported annual number of UK sporadic CJD deaths.[3, 5] Furthermore, surveillance in the UK has shown no increase in the proportion of sporadic CJD cases that are homozygous for methionine (Will RG, National CJD Surveillance Unit, United Kingdom, 2003; personal communication).
References
1. Gibbons RV, Holman RC, Belay ED, Schonberger LB. Diagnosis and reporting of Creutzfeldt-Jakob disease. JAMA 2001;285:733-734.
2. Belay ED, Maddox RA, Gambetti P, Schonberger LB. Monitoring the occurrence of emerging forms of Creutzfeldt-Jakob disease in the United States. Neurology 2003;60:176-181.
3. Belay ED. Transmissible spongiform encephalopathies in humans. Annu Rev Microbiol 1999;53:283-314.
4. Asante EA, Linehan JM, Desbruslais M, et al. BSE prions propagate as either variant CJD-like or sporadic CJD-like prion strains in transgenic mice expressing human prion protein. EMBO J 2002;21:6358-6366.
Competing Interests: None declared.
doi:10.1016/S1473-3099(03)00715-1 Copyright © 2003 Published by Elsevier Ltd. Newsdesk
Tracking spongiform encephalopathies in North America
Xavier Bosch
Available online 29 July 2003.
Volume 3, Issue 8, August 2003, Page 463
“My name is Terry S Singeltary Sr, and I live in Bacliff, Texas. I lost my mom to hvCJD (Heidenhain variant CJD) and have been searching for answers ever since. What I have found is that we have not been told the truth. CWD in deer and elk is a small portion of a much bigger problem..” ............................
FRIDAY, NOVEMBER 30, 2018
The European Union summary report on surveillance for the presence of transmissible spongiform encephalopathies (TSEs) in 2017
THURSDAY, OCTOBER 04, 2018
Cervid to human prion transmission 5R01NS088604-04 Update
Sunday, September 16, 2018
Mother to Offspring Transmission of TSE PRION DISEASE and risk factors there from
MONDAY, NOVEMBER 26, 2018
Sporadic Creutzfeldt-Jakob Disease in a Woman Married Into a Gerstmann-Sträussler-Scheinker Family: An Investigation of Prions Transmission via Microchimerism
WEDNESDAY, OCTOBER 17, 2018
PRICE OF TSE PRION POKER GOES UP spectrum of human prion diseases may extend the current field and may notably include spinal cord diseases
0 Comments:
Post a Comment
Subscribe to Post Comments [Atom]
<< Home